Elements each using a current-perpendicular-to-plane giant magneto-resistance effect (referred to also as a CPPGMR hereinafter) of a thin film having a trilayered structure of a ferromagnetic metal/a nonmagnetic metal/a ferromagnetic metal have been expected for readout heads for magnetic disks. Researches have been made about elements each using a Heusler alloy, which is large in spin polarizability, as each of the ferromagnetic metals. A development has been made about a CPPGMR element using a polycrystalline thin film having a crystal orientation textured into a (110) direction as a layer of the Heusler alloy (for example, Patent Literatures 1 to 3).
By contrast, it is demonstrated that in a CPPGMR element, the use of a monocrystalline thin film textured into a (100) direction makes it possible to improve performances of the element (for example, Non Patent Literatures 1 and 2). However, for the production of the monocrystalline thin film, an expensive MgO monocrystalline substrate is required, and thus such methods are impracticable from the viewpoint of costs.